Acyclic carbene ligand for ruthenium complex formation, ruthenium complex catalyst, and use thereof

A ruthenium complex catalyst having a structure of Chemical Formula 3:

• wherein, in Chemical Formula 3,
• R1 and R2 are each independently a hydrogen atom, a substituted or unsubstituted C1-C6 alkyl group, C3-C8 cycloalkyl group, or C6-C10 aryl group;
• or R1 and R2 are connected to each other to form an unsubstituted or substituted 4- to 8-membered heterocycle with a nitrogen atom to which they are connected,
• R3 and R4 are each independently a hydrogen atom, a substituted or unsubstituted C1-C6 alkyl group, C1-C6 alkenyl group, C1-C6 alkynyl group, C3-C8 cycloalkyl group, or C6-C10 aryl group,
• R5 is a hydrogen atom or C1-C6 alkyl group,
• R6 and R7 are each independently a halogen,
• R8 is a substituted or unsubstituted C1-C10 alkyl group, C5-C10 carbocycle, or 5- to 10-membered heterocycle,
• R9 and R10 are each independently a C1-C10 alkyl group, or are connected to each other to form a C5-C10 carbocycle or a 5- to 10-membered heterocycle, and
• R11 is N or O.

A method of preparing a ruthenium complex catalyst, the method comprising the steps of:

• treating formamide with oxalyl chloride to obtain an intermediate;
• reacting the intermediate with alkoxysilane to obtain an acyclic carbene ligand having a structure of Chemical Formula 1;
• and
• binding the ligand with ruthenium to form a ruthenium complex catalyst having a structure of Chemical Formula 4:
• wherein, in the above Chemical Formulae,
• R1 and R2 are each independently a hydrogen atom, a substituted or unsubstituted C1-C6 alkyl group, C3-C8 cycloalkyl group, or C6-C10 aryl group;
• or R1 and R2 are connected to each other to form an unsubstituted or substituted 4- to 8-membered heterocycle with a nitrogen atom to which they are connected,
• R3 and R4 are each independently a hydrogen atom, a substituted or unsubstituted C1-C6 alkyl group, C1-C6 alkenyl group, C1-C6 alkynyl group, C3-C8 cycloalkyl group, or C6-C10 aryl group,
• R5 is a hydrogen atom or C1-C6 alkyl group, and
• R8 is a substituted or unsubstituted C1-C10 alkyl group, C5-C10 carbocycle, or 5- to 10-membered heterocycle.